In each of the three moments captured in the images below, Jimmy Kimmel is suppressing tears while describing what David Letterman and his show meant to him. When attempting to squelch such emotion, one common nonverbal signal is a jaw jut clustered with a dimpling of the chin. In addition the lips will often take on an appearance as seen here - thinned and sometimes with a concave-down configuration such that a novice of body language may indeed mistake this for anger or bitter regret.
It is also very noteworthy that at each of these moments of more intense emotional display - when his face was more tense - so were Kimmel's hands - for then they were held the together in a very common example of a MAP (Manipulator, Adaptor, Pacifier). This is another example of body language in the midst of attempting emotional suppression (ergo the descriptor "pacifier" [Navarro]). It's a very common nonverbal phenomenon - that when the mouth and mid-face develop tension - the hands will also display it.
This was a classy tribute on Jimmy's part. Said another way - and from a nonverbal perspective, Kimmel's sincerity quotient was very high. There are many times when such emotion is feigned - but this was NOT one of them (When was the last time you were fooled?).
Thank you David Letterman.
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